Rob, much of the information came from my transcription of the Compiled Service Records of the 18th (Marmaduke's) Arkansas Infantry. Additional information can be found in the CSRs of the 3rd Confederate Infantry, which I haven't personally transcribed but have seen someone else's trascription, and is basically a continuation of the records of the old 18th Arkansas.

The CSRs I transcribed can be found on Rolls 159-160 of Microcopy 256 of the "Compiled Service Records of Confederate Soldiers Who Served in Organizations From the State of Arkansas."

In April 1862, Colonel David W. Carroll's newly-organized regiment was given the unused 18th Arkansas designation that had been previously assigned to Marmaduke's regiment (now the 3rd Confederate). As a result, the records of the two regiments are sometimes confused with one another.